Congrats on 6 weeks, that is a big deal!! Remember, you numbed your emotions with booze and now you're not, so they're bound to bubble over once in awhile.
It sounds like you have a lot on your plate so try to cut yourself some slack.
I broke down in tears today too-overwhelmed with responsibilities,finances,etc. so I can totally relate. I can pretty much say that tomorrow will be better, barring any disasters lol I hope the same for you.
Kids are resilient. Give your daughter a special treat to make up for being angry today and reassure her that you were just having a grumpy day and it wasn't her fault. I think it's good for children to see adults express emotions and explain feelings. So many try to hide them from kids and then wonder why the kids don't express themselves or handle feelings better later in life.